The present invention relates to a pharmaceutical composition of the treatment of inflammatory skin conditions, and a therapeutic method for treating inflammatory skin conditions using the pharmaceutical composition.
Topical corticosteroids are a powerful tool for treating skin disease. Understanding the correct use of these agents will result in the successful management of a variety of skin problems. There are many products available, and new ones appear almost monthly. Pharmaceutical companies have responded to the great demand for these agents with an increasing number of products, but all of these preparations have basically the same antiinflamatory properties. They differ only in strength, base and price.
The antiinflammatory properties of topical corticosteroids result in part from their ability to induce vasoconstriction of the small blood vessels in the upper dermis. This property is used in an assay procedure to determine the strength of each new product. These products are subsequently tabulated in seven groups, with group I the strongest and group VII the weakest (see the Formulary below).
The treatment recommends topical steroids by group number rather than by generic or brand name because the agents in each group are essentially equivalent in strength. When a new topical corticosteroid appears on the market, ask to which group it belongs and add it to the list in the Formulary.
Guidelines for choosing the appropriate strength of topical steroid are presented in the chart below.
The best results are obtained when preparations of adequate strength are used for a specified length of time. Weaker, xe2x80x9csaferxe2x80x9d strengths often fail to provide adequate control. Patients who do not respond after 1 to 4 weeks of treatment should be reevaluated.
Additionally, topical preparations of the steroid clobetasol propionate are indicated for the relief of the inflammatory and pruritic manifestations of cortico-steroid-responsive dermatosis. See, for example, Maloney, et.al., xe2x80x9cClobetasol Propionate Emollient 0.05% in the Treatment of Atopic Dermatitisxe2x80x9d, International J. of Dermatology, 1998, 37, 128-144.
In the past, it has been found that clobetasol propionate is most effective in the treating of inflammatory skin conditions when combined with zinc pyrithione and undecylenic acid. For example, Seidel (U.S. Pat. No. 5,972,920) discloses the use of clobetasol propionate in combination with either zinc pyrithione, undecylenic acid, or both. Applicant Crutchfield also noted the requirement for zinc pyrithione in Crutchfield, et.al., xe2x80x9cThe Effective Use of Topical Zinc Pyrithione in the Treatment of Psoriasis: a Report of Three Casesxe2x80x9d, J. Geriatr. Dermatol. 1997; 5(1):21-4.
Surprisingly, the applicants have found that zinc pyrithione and undecylenic acid are not necessary for the optimal effectiveness of clobetasol propionate.
Studies have also indicated that some sort of surfactant, such as sodium lauryl sulfate, is necessary for the optimal effectiveness of clobetasol propionate, whether alone or combined with zinc pyrithione and undecylenic acid. Again, Seidel ""920 discloses the use of an anionic surfactant (sodium lauryl sulfate) in conjunction with clobetasol propionate, zinc pyrithione, and undecylenic acid.
Surprisingly, the applicants have found that no surfactant is necessary for the optimal effectiveness of clobetasol propionate.
Applicants have also found that the composition is most effective and easily tolerated by patients when administered in a spray form by means of a propellant. In contrast, Seidel ""920 teaches away from the use of a spray as being highly evaporative and producing a painful freezing sensation to the skin and that some propellants are explosive.
A pharmaceutical topical spray composition of corticosteroid, an alcohol, a propelant, and isopropyl myristate. A method for treating an inflammatory skin condition using the administration to the skin of a mammal of the pharmaceutical composition. The pharmaceutical composition is effective in the treatment of inflammatory skin conditions without the need for zinc pyrithione, undecylenic acid, or a detergent.